Attachment for grinding-machines.



M. WAGNER. ATTACHMENT FOR GRINDING MACHINES.

APPLICATION FILED JUNE 2, 1913,

593 Patented June 30, 1914 lrtiiluiu WITNESSES INVENTOR COLUMBIAPLANOGRAPH CO.,WASHINOTON. 0.6.

nrnn srnrwnnr rre.

MICHAEL WAGNER, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO SAMUEL S.NEWMAN, OF PITTSBURGH, PENNSYLVANIA.

ATTACHMENT FOR GRINDING-MACHINES.

Original application filed March 26, 1912, Serial No. 686,413.

Serial No. 771,180.

To all whom it may concern:

Be it known that I, MIoHAnL WAGNER, a citizen of the United States,residing at Pittsburgh, in the county of Allegheny and State ofPennsylvania, have invented certain new and useful Improvements inAttachments for Grinding-Machines, of which the following is aspecification.

The invention relates to grinding machine attachments, and particularlyto an attachment for holding drills while being ground; and the presentapplication constitutes a division of my application Serial Number686,413, filed March 26, 1912. The invention has for its primaryobjects; the provision of an improved drill holder capable ofaccommodating drills of widely varying lengths and widths; the provisionof a drill holder of simple, cheap construction which can be readily andconveniently adjusted to fit anysize of drill; the provision of a drillholder for flat drills in which improved means are provided for movingthe drill longitudinally during the grinding operation; and theprovision of improved means for securely and rigidly holding the shankof the attachment. Certain embodiments of the invention are illustratedin the accompanying drawings, wherein Figure 1 is a perspective View ofthe grinding machine with my improved attachment applied thereto, Fig. 2is a plan view of the attachment, Fig. 3 is an end view of theattachment, Fig. 4 is an enlarged section through the socket whichcarries the shank of the attachment, and Fig. 5 is plan view of amodified form of attachment.

As shown in Fig. 1, 1 is the grinding wheel which may be of any desiredabrading material and mounted on the shaft 2; 3 is a gear casing forcarrying the gears for driving the wheel 1 at a high rate of speed, fromthe driving shaft or spindle 4, and 5 is the operating handle.

The attachment which comprises the invention includes the mainsupporting framework 6 and a shank or bar 7 which slidably engages asocket in the cast lug 8 integral with one of the parts of the gearcasing 3. As indicated most clearly in the cross sec tional view of Fig.4, the bar 7 is provided with a flat face 9 which is adapted to beengaged. by the holding screw 10 so that the clamping force which isapplied to the bar is applied diagonally and tends to force theSpecification of Letters Patent.

Patented June 3%, 1914.

Divided and. this application filed June 2,

two sides 11 and 12 of the bar against the corresponding walls of thesocket, a recess 13 in the socket being provided opposite the cornerformed by the intersection of the sides 11 and 12. This arrangementsecures a much firmer support for the bar than is the case where theholding screw comes opposite one side only of the bar, the recess 13permitting the sides 11 and 12 to be forced inwardly so that theycontact firmly with the two sides of the socket.

Upon the upper face of the supporting portion 6 are mounted the jaws 14and 15, which jaws are adapted toguide the sides of the flat drill l6and are provided with downwardly projecting studs 17 and 18 engaging thediagonal. slots 19 and 20 in the part 6, and adapted to cause a movementof the jaws 14 and 15 toward each other when the studs 17 and 18 arepulled to the rear. These studs are pulled to the rear by means of aU-shaped frame 21 provided with two transverse slots 22 and 23 engagingthe studs 17 and 1S and having an arm 24 extending to the rear andadapted to be clamped in any desired position by means of the thumbscrew 25. The member 21 may be moved to the rear to cause the jaws 14and 15 to approach each other and engage the drill by means of thehandle 26 which projects laterally from the arm 24.

Slidably mounted in the rear portion of.

the member 6 is a bar 27, which bar may be rigidly held in any desiredposition of adjustment by means of the thumb screw 28. The rear end ofthis bar 27 is provided with an upwardly projecting lug 29 carrying thestud 30. This stud is provided with an operating handle 31 and thehandle and stud are normally yieldingly held in the position indicatedin Fig. 3 by means of a pin 32 which is yieldingly pressed against thefiat side of the stud 30 by means of the spring 33.

The operation of the attachment just described is as follows: The thumbscrews 25 and 28 being loose to permit free longitudinal movement of theparts 21 and 27, the drill 16 is placed in position so that its end justtouches the edge of the grinding wheel 1. The bar 27 is then movedforward so that the end of the stud 30 engages the rear end of thedrill, the handle 31 at this time occupying the position shown in Fig.3. The thumb screw 28 is then operated to clamp the bar 27 in position,and the handle 26 of the member 21 is drawn to the rear to cause thejaws l4 and 15 to move toward each other and engage the sides of thedrill, after which the thumb screw 25 is tightened. The handle 31 isthen moved a partial revolution to the left to carry the stud 30slightly to the rear and permit the drill 16 to move to the rear in casethe grinding Wheel 1 is not entirely uniform in diameter. Then as thegrinding wheel is rotated the handle 31 is moved from the position 34indicated in dotted lines in Fig. 3 to the position 35 indicated indotted lines, thus advancing the stud 30 and the drill as the grindingprogresses. This operation secures the grinding of one of the cuttingfaces of the drill, and the grinding of the other cutting face issecured by merely turning the drill upside down and repeating theforegoing operation insofar as the handle 31 is concerned, theadjustment of the bar 27 remaining the same.

It will be understood that the jaws 14 and 15 merely act as guides forthe drill and do not prevent free relative movement of the drilltherebetween, such drill being held firmly down in position by the freehand of the operator. The outer inclined faces of the jaws l4 and 15 areguided and supported by means of the flanges 36 and 37 upstanding fromthe base of the supporting frame 36.

An alternative arrangement for operating the jaws 14 and 15corresponding to the jaws 14 and 15, is shown in Fig. 5. In thisconstruction the supporting frame 6 is provided with transverse slots 38and 39, which slots are engaged by downwardly projecting pins 40 and 41upon the jaws 14 and 15. A pair of lever arms 42 and 43 are pivoted tothe under side of the frame 6 at 45 and 46, and the front ends of theselevers are positioned so as to engage the sides of the pins 40 and 41.The other ends of the levers 4.2 and 43 are adjusted by means of a wedge47 which. is slidable longitudinally of the bottom of the supportingmember 6 and is held in any desired position of adj ustment by means ofa thumb screw 48.

What I claim is 1. A flat drill holder for use with a grinding machine,comprising a support, a pair of jaws carried thereby for guiding theopposite edges of the drill, a slide carried by the support andadjustable toward and from the grinding wheel, means for locking theslide in any adjusted'position, and a screw mounted in the slide andadapted to engage the rear end of the drill whereby the drill may beadjusted longitudinally.

2. A flat drill holder for use with a grinding machine, comprising asupport, apair of jaws carried thereby for guiding the opposite edges ofthe drill, a slide carried by the support and adjustable toward and fromthe grinding wheel, means for locking the slide in any adjustedposition, a screw provided with a handle and mounted in the slide andadapted to engage the rear end of the drill, and spring means wherebythe handle and screw are maintained yieldingly in one position.

3. A flat drill holder for use with a grinding machine, comprising asupport, a pair of jaws carried thereby for guiding the opposite edgesof the drill, means for adjusting the jaws toward and from each other, aslide carried by the support, means for clamping it in any desiredposition of adjustment, and an adjusting screw carried by the slide forengaging the rear end of the drill.

4. A. flat drill holder for use with a grinding machine, comprising asupport, a pair of jaws carried thereby'for guiding the opposite edgesof the drill, a slide movable transversely to the path of movement ofthe jaws, connections between the slide and jaws for causing the jaws tomove relatively when the slide is moved longitudinally, means forclamping the slide in position, and means for adjusting the drilllongitudinally between the jaws.

The combination in a grinding machine having a socket, an attachment, asup porting post therefor of a cross section such that a Hat side liesopposite the intersection of two other sides and fitting the saidsocket, and a holding screw extending through the wall of the socket andengaging one of the sides of the supporting post opposite one of thecorners of the post, the socket being recessed at such corner so as tobe spaced away therefrom.

In testimony whereof I have hereunto signed my name in the presence ofthe two subscribed witnesses.

M. TAGNER.

Witnesses I Ancrrwonrrr MARTIN, LETITIA A. MYERS.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of latents'.

' Washington, D. C.

